JPH01304111A - Cold-setting resin composition - Google Patents

Abstract

PURPOSE:To improve the hardness at low temp. and hardness under high moisture of the obtd. cured product by compounding a specified polymer and a curing agent. CONSTITUTION:A linear polymer (A) contg. epoxy groups and having Si bound with a hydrolyzable group on its side chains or terminals of the linear molecule is obtd. by copolymerizing a vinyl monomer (a) contg. an epoxy group [e.g., glicydyl (meth)acrylate], a compd. (b) having a polymerizable double bond and no Si (e.g., methyl methacrylate) and a silane compd. (c) having a polymerizable double bond and a hydrolyzable group (e.g,, 3- methacryloxypropyltrimethoxysilane). Separately, a curing agent (B) is obtd. by reacting a hydrolyzable silane compd. (d) contg. an amino group (e.g., 3- aminopropyltriethoxysilane) with a hydrolyzable silane compd. (e) contg. an epoxy group (e.g., 3-glycidoxypropyltrimethoxysilane) and thereafter partially hydrolyzing the reacted product. The component A, the component B and, if necessary, an alkoxysilane crosslinking agent (C) which is a hydrolyzable silane compd. are compounded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a room temperature curable resin composition, and more particularly to a room temperature curable resin composition that is particularly useful as a coating material that provides a cured product with high hardness.

[Conventional technology]

Conventionally, room-temperature curing paints have been mainly used for woodworking and plastics. For example, for woodworking, there are two-component reactive acrylic urethane paints that use acrylic polyol as the main ingredient and polyisocyanate prepolymer as the curing agent. .

In addition, as a room-temperature curing composition containing a silicon compound, a composition consisting of a vinyl resin containing a hydrolyzed silyl group at the terminal or side chain and a curing catalyst (% 17295
No. 0, Japanese Unexamined Patent Publication No. 58-157810) are known.

Furthermore, in a vinyl polymer having a basic nitrogen atom, a compound having an epoxy group and a hydrolyzable silyl group in one molecule as a curing agent and a hydrolyzable silyl group as an essential group without containing an epoxy group. A composition (JP-A-61-225244) in which a compound containing a silanol group and/or a compound containing a silanol group is blended is also known.

[Problem to be solved by the invention]

Incidentally, in recent years, in order to prevent scratches on the surface of high-quality furniture, there has been a desire to develop a wood coating with high hardness. Also,
In the field of plastics, there is also a need for room-temperature curing paints that can provide higher hardness.

However, the hardness of the cured products obtained using the above-mentioned conventional compositions is insufficient (low-temperature curing is insufficient), and the hardness is easily affected by humidity, especially under high humidity. There was a problem that hardness decreased.

[Means to solve the problem]

The present inventors have made extensive research efforts to solve the above-mentioned drawbacks of the conventional technology, and have developed a polymer containing an epoxy group and having a silicon atom bonded to a hydrolyzable group at the end of a side chain or chain molecule. The present invention was completed by discovering partial hydrolysis of a reaction product between a hydrolyzable silane compound containing an amino group and a hydrolyzable silane compound containing an epoxy group as a curing agent.

That is, the present invention comprises: a linear polymer containing an epoxy group and having a silicon atom bonded to a hydrolyzable group at the end of a chain molecule; and a hydrolyzable silane compound containing an amino group. The composition of the present invention is a room-temperature curable resin composition comprising: a curing agent (6) mainly composed of gold, a partial hydrolyzate of a reaction product with a hydrolyzable silane compound containing an epoxy group; Polymers containing an epoxy group as a main element and having a silicon atom bonded to a hydrolyzable group at the end of a side chain or a chain molecule are It can also be adjusted by synthesizing a polymer and introducing a silicon atom having a hydrolyzable group into the polymer through a hydrosilylation reaction between this and a silane compound having a hydrogen atom bonded to silicon and a hydrolyzable group. However, by copolymerization of a vinyl monomer containing an epoxy group, a compound having a polymerizable double bond and no silicon atom, and a silane compound having a polymerizable double bond and a hydrolyzable group. Adjustment is easy and preferable.

Among the raw materials used in the present invention, typical examples of epoxy group-containing vinyl monomers include glycidyl acrylate and glycidyl methacrylate.

Typical examples of the polymerizable double bond-free compound and no silicon atom include methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, n-butyl methacrylate, n-butyl acrylate, and 2-ethylhexyl methacrylate. , 2-ethylhexyl acrylate, lauryl methacrylate, lauryl acrylate, cyclohexyl methacrylate, cyclohexyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, and other methacrylic esters and acrylic esters, as well as methacrylic esters. acid, acrylic acid, acrylonitrile,
Examples include aromatic vinyl monomers such as fumaric anhydride, styrene, and vinyltoluene.

Typical examples of the silane compounds having a polymerizable double bond and a hydrolyzable group include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-methacryloxypropyltrimethoxysilane, etc. can be mentioned.

Next, examples of hydrolyzable silane compounds containing amino groups include N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-
Examples include 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane.

Examples of hydrolyzable silane compounds containing epoxy groups include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. Examples include silane.

The room temperature curable resin composition of the present invention may also contain an appropriate amount of a hydrolyzable silane compound as an alkoxysilane crosslinking agent. Alternatively, both or a mixture thereof can be mixed.

Examples of the hydrolyzable silane compound as the alkoxysilane crosslinking agent include alkyl silicates such as ethyl silicate and methyl silicate; partially hydrolyzed condensates of the alkyl silicates; Alkoxysilane, alkenyltrialkoxysilane, of which vinyltrimethoxysilane is a typical example;
Phenyltrimethoxysilane? Representative examples include phenyltrialkoxysilane and the like, and partially hydrolyzed condensates of the triplekoxysilanes.

Next, what about the room temperature curable resin composition of the present invention? : Describe the manufacturing method.

First, the polymeric material is preferably a compound having a monovalent double bond with a vinyl monomer containing an epoxy group and having no silicon atom (hereinafter referred to as "other vinyl monomer"). ) and a silane compound having a polymerizable double bond and a hydrolyzable group (hereinafter referred to as "polymerizable silane compound"). A linear copolymer having a silicon atom bonded to a functional group is obtained.

In copolymerization, the proportion of monomerizable silane compounds in the total monomers (i.e., the total amount of vinyl monomers containing epoxy groups, other vinyl monomers, and polymerizable silane compounds) is ~30X mass%, preferably 5 to 203% by weight, and the proportion of vinyl monomers containing epoxy groups in the total monomers is 5 to 60% by weight, more preferably 10 to 40% by weight. It is preferable to carry out the copolymerization so that the ratio is below the lower limit or above the upper limit, and the stability of the resin composition of the present invention may be affected. reduction or fl of the cured product of the composition
This is not preferable because there is a tendency for deterioration of the appearance of the coating film such as a decrease in color or whitening to be observed.

For the copolymerization of the above-mentioned vinyl monomer containing an epoxy group, other vinyl monomers, and polymerizable silane compounds, any conventionally known one-polymerization method can be applied, but radical polymerization in an organic solvent can be applied. is the simplest and easiest method.

The organic solvent to be removed may be an inert organic solvent as long as it does not affect the stability of each compound used in the present invention or each reaction in producing the composition of the present invention.
This is advantageous in that the copolymerization reaction can be controlled easily and smoothly. Examples of such solvents include toluene, xylene, cyclohexane, n-hexane, various hydrocarbons such as high-boiling aromatic hydrocarbon solvents, methanol,
Ethanol, Impropertool n -Propertool,
Alcohol-fi such as n-butanol, inbutanol, S-butanol, ethylene glycol monomethyl ether, etc.
Examples include esters such as yM, methyl acetate, ethyl acetate, n-butyl acetate, and ethyl cellosolve acetate, and these can be used alone or in combination.

Curing agent Q3) can then be produced as follows. First, a hydrolyzable silane compound containing an amino group and a hydrolyzable silane compound containing an epoxy group are reacted, and then the reactants are hydrolyzed. ,At this time,
An amino group-containing silane compound and an epoxy group-containing silane compound are reacted such that the ratio of amino groups to epoxy groups is preferably 1:1 to 3:1 in molar ratio, and preferably the amino group-containing silane compound and the epoxy group are reacted in a molar ratio of 1:1 to 3:1. It is preferable to perform hydrolysis so that the amount of OH is 0.05 to 0.3 times the mole of all hydrolyzable groups in the group-containing silane compound.Under conditions outside these ranges, Even if the range exceeds the upper limit, there is a tendency for a decrease in the stability of the resin composition of the present invention, a decrease in the hardness of the cured product of the composition, or a deterioration in the appearance of the coating film such as whitening. Therefore, it is difficult to obtain the best results. This partial hydrolyzate is used as the main component, and the above-mentioned organic solvents are added and mixed for conditioning.

In this case, alkyl silicates such as methyl silicate and ethyl silicate; partially hydrolyzed condensates of the alkyl silicates; alkyltrialkoxysilanes such as methyltrimethoxysilane, and alkenyls such as vinyltrimethoxysilane; Hydrolyzable alkoxysilanes such as trialkoxysilane, phenyltrialkoxysilane typified by phenyltrimethoxysilane, or partially hydrolyzed condensates of the trialkoxysilanes can also be added as an alkoxysilane crosslinking agent. . The amount to be used at this time is not limited, but it is preferred, and it is preferably 1/15 to 1/2 at a ratio of 1.1 to the partial hydrolyzate of the main component. If it is less than 1/15, the coating film hardness is high.ζ
1: <<, If the content exceeds 1/2 gold, poor appearance of the coating film is likely to occur.

Hydrolyzable alkoxysilanes as alkoxysilane crosslinking agents can be added to the polymer matrix instead of the curing agent CB), or can be added to both the polymer (4) and the curing agent mixture Q3). It may be used by adding it, or it may be added to a mixture of both.

Although the room-temperature curable resin composition of the present invention has good curability even without mixing a curing catalyst, it can be cured by using a special catalyst to hydrolyze and condense each of the hydrolyzable silane compounds. , it is possible to fully accelerate the curing reaction and further improve low-temperature curability. Typical hydrolytic condensation catalysts (c) include basic compounds such as sodium hydroxide, potassium hydroxide, sodium methylate, tetramethylammonium hydride, tetraisopropyl titanate, aluminum acetylacetone, and octyl. Metal salts of organic acids such as tin acid, octylzinc, calcium octylate, lead naphthenate, dibutyltin diacetate, dibnaltin dilaurate, dibutyltin simalate, and acidic compounds such as p-toluenesulfonic acid, trichloroacetic acid, and phosphoric acid. etc.

It may be used in addition to the hydrolytic condensation catalyst (Q is the curing agent) or the alkoxysilane crosslinking agent, or a mixture of the polymer and the curing agent Q3) or the polymer (A).
, a curing agent (B), and an alkoxysilane crosslinking agent.

The room-temperature curable resin composition of the present invention comprises the polymer (4) prepared as described above and the curing agent) in a ratio of amino groups to epoxy groups contained in both components. Mix so that the molar ratio is 1.0 to 2.0,
Furthermore, if necessary (adding a hydrolysis condensation catalyst as component 0, about 0.001 to 1% by weight based on the total amount of the polymer composition and curing agent mixture (B) including the solvent) The room-temperature curable resin composition of the present invention, which is preferably produced by, further contains organic or inorganic dyes or pigments, a matting agent,
It is also possible to blend various additives such as ultraviolet fy absorbers, fillers, and flow regulators, and these additives do not inhibit the curing reaction of the room temperature curable resin composition of the present invention. There is no problem as far as it goes.

The room temperature curable resin composition of the present invention is applied to various base materials and then dried at room temperature to give a cured product with high hardness; however, if it is necessary to further accelerate the curing speed. It is not something that can prevent heating.
This does not mean that the benefits obtained will be diminished.

The room temperature curable resin composition of the present invention obtained as described above can be widely used as a paint, a surface modifier, a filler, etc. for wood products, various plastic products, etc.

〔Example〕

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited by these Examples.

In addition, in the following examples, all parts and percentages are based on weight unless otherwise specified.

(Preparation of Polymer (A')) Preparation Example 1 100 parts of xylene and 50 parts of n-butanol were charged into a reactor equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, and the mixture was heated at 9° under a nitrogen atmosphere. After heating to C, 40 parts of methyl methacrylate, 20 parts of glycidyl methacrylate,
10 parts of cyclohexyl methacrylate, 207 M of n-butyl acrylate, 2 parts of 2-hydroxyethyl acrylate, 1 part of acrylic acid, 10 parts of 3-meccryloxybrobyltrimethoxysilane (hereinafter referred to as MOPS-M), and sulfur oxide A mixed solution consisting of 2.5 parts of a catalyst (NOF (7) product, trade name ``Niver BMT■'' (peroxide 20%)) was dropped over a total of 3 hours.The temperature was maintained at the same temperature for 3 hours after the dropwise addition was completed. A polymer with a resin content of 40% (
A solution of A'-1) was obtained.

Preparation Examples 2 to 4 Usage amount (parts) of vinyl monomer and polymerizable silane compound
Polymers (A'-2) to (A'-4) were obtained in the same manner as in Preparation Example 1, except for changing as shown in Table 1.

Table 1 Composition ratio of polymer (A') However, MMA: methyl methacrylate GMA nigericidyl methacrylate cHMA dichlorohexyl methacrylate n-BA: n
-Butyl acrylate 2-HEA: 2-hydroxyethyl acrylate AA
Niacrylic acid.

(Adjustment of curing agent (mixture) (B)) 3-Aminopropyltriethoxysilane 120
After heating to 80℃ under nitrogen atmosphere, 3-
64 parts of glycidoxypropyl trimethoxysilane was added dropwise over 2 hours. After the dropwise addition was completed, the same temperature was maintained for 3 hours to obtain a solution of compound (B-1).

150 parts of this compound (B-1) and 150 parts of 2-ethoxyethanol were charged into a reactor equipped with a TFI stirrer, a thermometer, and a reflux condenser, and 6 parts of atoa was added dropwise at room temperature. After stirring for one day and night, a curing agent (B-2) was obtained.

A curing agent mixture (B-3)' was obtained by mixing 10 parts of an ethyl silicate partial hydrolyzate (ES-4 (1) manufactured by Nippon Colcoat Co., Ltd.) with 90 parts of this curing agent (B-2).
) and 0.1 part of dibutyltin diacetate was added and mixed to prepare a curing agent mixture (B-4).

Examples 1 to 4, Comparative Example 1.2 Polymers (A'-1) to (A'-
After diluting the solution of 4) to an active ingredient concentration of 35% by adding a 1:1 mixed solvent of toluene and butyl acetate, add curing agent (mixture) (B-2) to (
A curable resin composition was prepared by adding and mixing B-4) in the amounts shown in Tables 2 and 3.

Next, this curable resin composition was coated on a glass plate with a bar coater so that the dry film thickness was about 10 μm, and the relative humidity was 79% Kv! with a saturated solution of NH and C1 under normal temperature and normal humidity and high temperature conditions. 4. Cured in a humid desiccator at 25°C to obtain each cured coating film. In order to evaluate the surface scratch resistance of each coating film thus obtained, pencil hardness was measured. The results are shown in Tables 2 and 3.

Table 2 Table 3 ``(Note) Pencil hardness: Measured according to the 8.4 pencil hardness test of JIS G-3312 (colored zinc plate), and the maximum hardness that does not cause scratches on the surface is indicated.

Here, Comparative Example 1 is an example in which the polymer (1) contains an epoxy group, and Comparative Example 2 is an example in which the copolymer is a silicon bonded to a hydrolyzable group among the constituent elements of the polymer (3). These examples lack atoms, and each has drawbacks such as low coating film hardness or poor coating film appearance (or coating failure).

(Effects of the Invention) As is clear from the above examples, the present invention makes it possible to obtain a cured product with high hardness at room temperature and even under high humidity. This will enable the early development of high-hardness paints, and the industrial benefits will be immeasurable.

that's all

Claims (6)

[Claims] (1) A linear polymer (A
) and a curing agent (B) whose main component is a partial hydrolyzate of a reaction product between a hydrolyzable silane compound containing an amino group and a hydrolyzable silane compound containing an epoxy group. thing. (2) The polymer (A) according to claim (1), the curing agent (B)
) and a hydrolyzable silane compound as an alkoxysilane crosslinking agent. (3) Room-temperature curing obtained by mixing a catalyst for promoting hydrolysis and condensation of a hydrolyzable silane compound in addition to the two components described in claim (1) or the three components described in claim (2). resin composition. (4) A linear polymer containing an epoxy group and having a silicon atom bonded to a hydrolyzable group at the side chain or chain molecule end,
It is obtained by copolymerizing a vinyl monomer containing an epoxy group, a compound having a polymerizable double bond and no silicon atom, and a silane compound having a polymerizable double bond and a hydrolyzable group. Claim (1) characterized by
The room temperature curable resin composition according to any one of (3) to (3). (5) The hydrolyzable silane compound used as the alkoxysilane crosslinking agent is ethyl silicate or a partially hydrolyzed condensate thereof. The room temperature curable resin composition according to any one of claims (2) to (4). (6) A curing agent whose main component is a partial hydrolyzate of a reaction product between a hydrolyzable silane compound containing an amino group and a hydrolyzable silane compound containing an epoxy group.